1: Prepare all ingredients by slicing the avocado, onions, mushrooms, bell peppers, and tomatoes.
2: Heat a non-stick skillet over medium heat.
3: Add the sliced vegetables to the skillet and sauté until softened.
4: Pour in the beaten eggs and cook until set, folding the omelette as necessary.
5: Serve the omelette topped with sliced tomatoes.
